Apparatus for testing storage-battery circuits.



mmof APPARATUS FORTESTING kSTORAGE BATTERY CIRCUITS.

APPLIQATON FILED SEPT. 24, 1910.

1,099,909. A aente June 16, 9.1%

n@ fxk A WlTNESSESI la l] n INENTQR /f Mg, www d yUNTTED sirname PATENT OFFICE.

CLARENCE E. BEACH, OF BINGHAMTON, NEW YORK,A ASSIGNOR T0 GEORGE 0. KNAEP,

OF NEW YORK, N.

APPARATUS FOB. TESTING STORAGE-BATTERY CIRCUITS.

To all lwhom it may conce/rn Be it known that I, Chinesen E. linacn, acitizen of the United States, residing Binghamton, in the county of Broome and State of New York, have invented certain 'new and useful Improvements in Apparat-us Aing and providing current for circuits to be I- supplied, while one or. more other sets ot batteries are being recharged.

Among the important objects of my invention are toprovide improved switching mechanism and circuit arrangement for enabling suitable measuring instruments to be readily and quickly associated in various ways with the batteries to test the condition of the batteries and the circuits connected therewith and controlled thereby, and to provide such switching mechanism and circuit arrangement that such testing'- may' be safely.accomplishedand so that the instruments Will not be subjected to harmful currentslow. In testing systems of this class a voltmeter and ammeter are usually employed for testing the conditions olt the batteries and the circuits connected therewith,

and among suchtests it becomes desirable to connect the volt-meter with the batteries and with the ground. The voltnictcijemployed usually has` a uieasuring capacity substantially the 'saine as. or not much greater "than, the inaxin'nun voltage output of the batteries, but in charging the batteries they are frequently charged from a.

circ-uit of much" higher potential. which cir- A,cuit may have one side normally grounded,

'or the batteries are connected with external circuits whose conductors aro apt to come in contact with higl'i voltage foreign circuits. Under such conditions it is veryiniportant that provision be made to prevent connection of the voltmeter between ground and any terminal of the batteries which are heilig charged, for it such connectionwere specification of Leners Patent.4

Application sied september 24, 1910. serial noxssssaRElSS Patented l une 1,6, 1914.

cuit became grounded, Very heavy current would flow through the voltmeter and injure or destroy it; It is equally important to prevent direct connection ot any terminal of the charging batteries with ground, as the batteries when under such conditions become seriously injured or even destroyed, due to current flow therethrough either in excess quantity or in the wrong direction.

Another very important object of my invention is, therefore, to provide such switch mechanism and testing circuits that it will be impossible to connect any terminal of the charging batteries directly with ground.

Referring to the accompanying drawings, Figure l is a diagrammatic plan View of the y entire. apparatus; Figs. 3 and 3 are end elevations, partly in section, of sliding contactmakers; and Fig. 4' is a side elevation oi' one of these contactmakers. v

Referring to Fig 1,'B1 and B2 are storage batteries,y the negative terminals of which are connected with the studs C1 and C2 re- 4spectivelyand thc positive terminalsl with of an aimnetershunt F1 is connected to the stud D", and the other end ot said shunt is connected to the stud E. ()ne end of anstud llefand the other end of said shunt F2 being rminectcd to the stud Ff. Circuits Grl and G2 containing signaling` or other appa gaius 2, Q which represent i'ivc alarm boxes of any usual construction, to be energized by the batteries are connected between the studs C1 and El and the studs C2 and E2, respectively. Two posts H1 and H2 are so `mounted as to support a horizontal rod Il in suitable relation to the studs C1 and CZ. Corresponding posts J1 and J2 support the rod K1 in similar relation to the studs D1 and D2, and thc posts L1 and lf" support the rod M in similar .relation to the studs E1 -and E2. A sliding block 01 (Fig. 2) is mounted -upon the rods l1. K1 and M1. said rods being arranged parallel to each other and the holes through the block 0 being of such sizexas to permit the block to slide freely upon the rods. Contact springs P1, P2 and P3 are carried by the block O11, one end -o a spring P1 being arranged to rest spring P1 to project-in the path of the studs C1, C2 and contact with the rounded sides of made dringa time that thecharging ciri said studs. The spring P2 is similarly the `studs D1 and l)2 respectively. One cndl Pilier ann'neter shunt lF2 is connected to the mounted with relation to the rod K1 and the studs D1, D2 and. D11 and the oprlng P3 is similarlyv 'lnrluntod Wlth relation to tho rod M1 and the studs E1, E1 and F, The studs C, D und E are arranged 4in parallel rows, the studs C1, C1 being in n, lino parallol to the :rod l1, io Studs D1, Dg and D3 in n lino pornllol to tho .rod K1, :ind the studs E1, ll? and. 'El :in a. lino parallel to the rod M1, The distance troni thostnd C1 to the stud C1 is the tontons the dintnnre from tho stud D1 to tho stud and that 'from tho stud E1 to the stud E2. The distance hotween tl studs D1 and D1, :ind E1 :1 nd l .is likewise equal. The springs l, P2 :1nd P11 are mounted in o lino with ono another on the insulating bloc/lt D1, so that Suid springs may sinulltnneously rest. upon the respective studs C1, D1 and E1, or tho studs C?, D1, and E1, or thol studs D1 and E11, und theroby form olootrionl connections botwoon said studs and the roda l1, K1, M1.

Two other storage butter-ins l5 :nld B* are ronnontoil to studs U1, D1, C5 sind D, 'and shunto F1 :und F* nro oonnocted to studs E4 and E in n. manner similar to that already described `with rolation to the, buttery B1 and shunt F1. The studs and En :rre nonnorted to charging-0ilrrent terminal Q1, and tho studs C1 and D. nro connected to the olmrging-oorront terminal Q1. A motor gener( or R, .or other snitnblo source Aof charging current. is oonnectod to the Studs Q1 ond Q" by moans oit the Winer, 5l. .Rods l2, K1 :ind lvl nro nioluitod in suitable relotion to the studs und C, said rods boing mounted between tho posts ll. and H1, the post-S J3 und J1 :1nd posts lf and L1 rospontivoly. il. sliding block 01 Similar to the blotlt O1 is carried h r ihrs@ rhds, .smid hloolt'boing); rquipprd with this springs P1", F11 ond P11. 'lho perth ot' tho rhnrgring @un ront 'trom the gamorntor 'R is tlnough ono ol tho wires S to the terminal Q1, tllonoo to the sinds i". :rnd lll". tl'iroug'h tho shunts F11 find F1 to .,hn stiuls D" nlnftDl -tlionvo throi'igh tho storugfo botto lt und B1, from the sit-nds C1' :1nd C Vto the terminal Q1, and through tho other wiro ,S buch to the ,gcnorzrtor ll. l

Tho .Stud D" mounted naar the. mll@ i ronnotrted by um?. oi tho u'iro l`1 with th post J1, und the stud it)3 rntmntod near th rod M1 in oonneoted by menus ol" the with tho pont L1. r11 stud C .mountod near the'rod l1 is Connected by moons ot' tho wir@ U1 with the sifitoh arm il, :t stud D mounted near tho rod K2 is connected by means of the wire UL with the switch v arm W1. The swith arms 71 und W1- ore connected by means of the insulating yoke. Z so that said otros -will move in unison. Gon tact-points ll, l2, 13 and 1.5i are mounted in the path of tho itch firm W1, :1nd con-- tnct-po1ntn ,121, 223, SM; and il" oro mounted in 'smilzir relation with the switchiarm W1.-

i The contacts 13 and 25 are respectively con` ing connected with tho post J by means of the wire V2. An animator A .is irovifled, on@ terminal ot' which 'is connected to tho oost, J1 by niensroftho wird-A1, the other terminal of said nmmoter hgingronnected to the post. 'L1 by means of tlifnnro A2. Said nmrnetr is so tnlihrntod flintwhen the posts J2, L2 nro Qonncotodhto thoA terminala of either of the shunts F1, l. F or F. the ummcter will .indirate the` volume of onrrnt passing; through the shunt. l'l'hile Fig. l. :is wired, requires the use of 117, conter zero alnrnoter, the reversal of the Wires T1 and l`2 at tho posts J1 :1nd L4 :id-opts" my invention 'tor use with on 0nd zero nmlnetcr.

In using my inrentifm, if it i9 desired to observo the voltage and :nnporge of th@ buttery B1, the sliding blocky moved along' tho rods I1, K1 and M1 nntil its spring P1 connects the stud C1 with the rod l1, tho spring l thon rounrfting tho stud D1 with the rod K1 :1nd the springy P1nominating thev stud l1 with the roll M1: the sliding` blot (l1 is also niovrd :donn` tho rods;l l1. K1 .find M1 to u, ositi -n whore its uonmct Spring P11 will sonnent tho stud C `with the rod ond the spring P21 will connect the stud D? with tho ,rod K2: und, tho switchnrmflv is nmvedfilb t position whore it upon tho rmitn'cl ,l l. thus bringing tho Switch arm W1 to nfnosition Where it rests upon tho uo-ntzut Tho Yoltumtor lv' will now indicnto tho f li'leronoe ot potential betu'oon tho trrniinols D1, C1 of tho battery B1 by tho 'following (fin ruit z-stud D1, spring-1F, rod KP. post J1, wire Y1, switch Contact 2l, switch arm W11, wir@ D?, stud D, spring P11, rodY K2, post J3.. wire X7 ltinetor V. Wire V1, post H, rod l?. spring P11, studf'. wire Ul., switch urn: 11. oontnct lll, wir(` Y1, vos. 1, rod l1, spring l, and stud 01. 'llhomjnnoterAalso indirntvs tho mirronlv ilmviflgnthrough the oirruit (l1 :1nd shunt F1 by the` following circuit :---stud D1, spring P1, rod K1, post J1, u'iro A1, nnnnetor A, wire A1', post L, rod' M1, spring P", und stud E1.

It it desired to determine the difference ot potential hetweentho positivo terminal U1 of the battery B1 and the""ground-X, the switch arm lV 1 is now mov so that'fii:` rests on Contact 13, switch arm then rest,- ng on the Contact 23. The circuit i then as :follows z-stud D1, spring P2, rod R post J1, wire Y, oontaot 23, ,switchi :frm W1,

v C1 of battery.' B1 andthe ground X, the

' the' position where the cuit between thev termlnals of said shunt F3 storage batteries.

and E1, respectively, wherebyA the Iammeter mentarily connect the wire Y2 with the wire wire U2, stud D6, sprin P21, rod K2, post J1, wire V2', voltmeter wire V1, post H3, rod I2, spring P11, stud C, wire U1, switch arm W1, contact 1,3, wires X2 and X1, ground X.

If itis desiredto measure the difference of potential between the negative terminal switch arm T1 is moved so that it rests on the., contact 15, switch arm W2 then restingon the contact- 25. The circuit is then as follows :-stud C1, spring P1, rod I1, post H1, wire Y1, contact 15, switch arm W1, wire U1, stud C, spring P11, rod I2, post H3, wire V1, voltmeter V, wire V2, post J3, rod K2, spring P21, stud D", `wire U2, switch arm W2, contact 25, `wire X1, ground X. If the insulating block O1 is now moved alongion the rods l1, K1, M1 until its springs .P1, P2, P3 rest upon the studs C2, D2, E2, respectively, similar tests of battery B2 may be made by correspending manipulation of the switch arms W1 and W2. v i

To test thediierence of potential between' the terminals of the battery B, the insulating block 02 is moved along thev rods I2, K2 and M2 until the Contact springs P11, P21, P31 rest against `the studs C4, D1, E, respectively. 'l1-he circuit is then as follows yr--stud D4, spring P21, rod`K2, ost J2, wire V2, voltmeter V, wi'e V1, post is, rod l2, spring P11, stud C4. It `will be evident that as soon as the insulating blocl02 is moved away from brushes P11, P21 rest against the studs C, D, respectively, no manipulation-@the switch arms W1 and lV2 will co ect th voltmeter V,:or cause the ground 4 to be-connected,vwitli any of the lt itdesired to indicate the current flowing through the battery B3, the insulatintf block 01 is now moved alongr the rods l1, K1 and M1 to a position where the springs P2 and P" are in contact with't-he studs D3 the fall A is so connected that it measures The cirof potential across the shunt is then as follows r-stud D4, spring P21 rod K2. post J4, wire T15 stud D2, spring P, rod K1, post J2, wire A1, ammeter A, wire A2, post- L2, rod M1, spring P3, stud E3. wire T2, post L4. rod `M2, spring P31', stud E4. Similar tests of battery B4 may be made by moving the insulating block O2 along the rods I1, K2 and M1' to a1 position where the springs P11. T221, P21 are in contact with the studs C5, D5, E5. respectively.

Contacts 12, 14, 2Q and Q4 are provided so that the switch arm W71 will vnot momentarily connect the wire Y1 with wire X2 when said switchI arm is being moved between the contacts 11 and 15 and contact 1B, and so that the switch arm W2 will not mov X1. lwhen said switch arm W2 is being moved between the contacts 23 and 25. This pre*- vents" the ground X being connected to either terminal of any of the batteries except through the voltmeter V. The same result can be obtained by keeping the contacts l1, 13 and l5 .at-such distance from eachotherthat the switch arm W1 cannot bridge between any Aof said Contacts, and keeping the contacts 23 and 25 a like distance apart with relation to the switch arm lVZ. l have however found it more oonvenient to provide the extra contacts shown, in order to prevent the switch arms catchingr b'etweenthe contact studs on'account ot' not being' supported, as when such studs are omitted.

From the foregoing description it is clear that in my testing' system the instruments can be quickly and readily connected for ascertaining the desired conditions ol the batteries and circuits, but at' the same time such adjustment of the switch mechanism is prevented as would allow the connection of any terminal of the charging batteries to ground either directly or through the voltmeter.

The batteries may therefore be charged from high' potential circuits which are normally grounded or which may become grounded at any time. Changes and modifications are of course possible which would still como Within the scope of the invention, and I do not therefore desire to be limited to the pre cise construction and arrangement shown. ln the claims l have referred for convenience to a charging battery;7 by which is meant afbattery which is receivingor has received a charge ot electric energy from a suitable generator; and to a dischargingl battery by which is meant a battery connected in circuit with one or more devices, ,such as signal-boxes, or other devices ttor consuming,T electrical energy` l claim:

l. .ln combination, a battery and work- .circuit connected thereto, a separate battery and battery-charging circuit, a voltmeter, a ground connection, means for coupling the voltmcter to opposite batteryfterminals-of either circuit, and means ior ygrounding either battery-terminal of the work-circuit through the voltmeter.

2. ln combination, a series of batteries and work-circuits connected thereto, a separate series of batteries and battery-charging circuits. a voltmeter, a ground connection, means toy coupling the voltmeter to opposite balterr-terminals oil either circuit, and means tor grounding either battery-terminal oi any worlecircuit through the voltmcter.

S. ln crnlbnation, a battery and workcirci 't connected thereto, a separate battery and haitervcharging circuit, an ammetcr .shunt in each circuit, a voltmcter, an amrneter, a ground connection, means for coumembers, and'comiections between the lasti Imentioned movable members and the indeiixed members connected to the terminals of said second ammeter shunt and movable members, arrange to engage said lined pendent Vpair of fixed terminals whereby the ammeter may connected acrosgl the shunt of either battery.'v

11. The combination with a volt-meter and va switch provided with a ground, ofa battery, a circuit-controller having connections to the terminals of said battery, a second battery, a circuit-controller forsaid second battery, said second circuit-controller having additional contacts independent of the battery terminals and circuits oonnecting the voltmeter with said second circuit-controller, circuits connecting the additional contacts of said second circuit-controller with the switch and circuits connecting the switch with the first-mentioned circuit-controller, the circuit connections being so ar ranged that the voltmeter may be directly connected with the terminals of either `battery or that either terminal of the first battery may be grounded through the voltineter. a Y

12. In a, storage battery system, the combination of a ldischarging battery, a charging battery, a roltmeter, a ground connection, means for connecting said voltmeter bet-Ween either terminal of the discharging battery and ground, means for connecting said voltmeter to the opposite terminals of the discharging battery and\means for disconnecting -the connections to said discharging battery and to ground, and connecting the voltmeter to the opposite terminals of theV charging battery. l 13. ln a storage battery system, the combination of a plurality of discharging batteries, voltmeter, a ground connection, means for connecting said voltmeter between either terminal of any discharging battery and ground, means for connecting said voltmeter to the opposite terminals of any discharging battery and means for disconnecting the connections to said discharging batteries and to ground, and connecting the voltmeter to the opposite terminals of any charging battery.

14. In a storage battery system, the combination of a discharging ,battery and discharging circuit, a charging battery and a charging circuit, an ammeter shunt in each circuit, an anime-ter, a voltmeter, a ground connection, means for connecting t-he voltmeter between either terminal of the discharging batteryy and ground, means `for connecting .said 'voltmeter to the opposite I' terminals oi.: the discharging battery, means for disconnecting the connections between said discharging battery and ground and connecting the voltmeter to the opposite a plurality of charging batteries, a-

terminals of the charging battery, and` means for connecting the ammeter to the terminals ot' either shunt.

15. In a storage battery system, the eom-, bination of a plurality of discharging batu teries, a plurality of charging batteries, an ammeter shunt connected in series with each battery, a roltmeter, an ammeter, a ground connection, means for connecting the volt meter between either terminal of any discharging battery and ground, means for connecting said voltnieter to the opposite terminals of any discharging battery,vmeans for disconnecting the connections to said discharging batteries and to ground and connecting the voltmeter to the opposite terminals of-any charging battery, and means for connecting the amineter t-o the terminals cfa-ny shunt. I

'16. In a storage battery system, the combination of charging and discharging batteries, a measuring instrument, a Aground connection, means whereby said measuring instrument-maybe operatively connected to said charging batteries or to said discharging batteries, and meanswhereby said measuring instrument, when connected to said discharging batteries, may be operatively connected to ground. l

17. In a storage battery system, thecombinatiou of charging batteries, discharging batteries, a measuring instrument, switc mechanism and circuits controlled thereby to connect said measuring instrument across the terminals of 'tiny discharging battery, and to connect said measuring instrument between any terminals of any discharging battery and ground, and switch mechanism to open said first named circuits and to connect said measuring instrument across the terminals of any charging battery.

18.- In a storage battery system, bination of charging and discharging batteries and a measuring instrument, a ground connection switch mechanism and circuits controlled thereby to connect said measuring instrument with either battery or with the discharging battery and ground and a1'- ranged to disconnect said instrument and said ground connection when connecting said instrumfnt to said charging battery.

19. In'a storage battery system, the combination of charging and discharging batteries, a setof switch bars associated with each battery, a movable switch member for each set of switch bars for connecting said bars with the terminals of the associated batteries, a measuring instrument connected with the switch`bars associated with the charging battery, a ground switch constructed and arranged to be connected to the switch bars of the charging battery Vby the associated switch member only when said the comswitch bars are disconnected from the terconnections between said ground switch and the switch bars of the discharging batteries.

20. In a storage battery system, the combination of charging batteries, discharging batteries, switch mechanism for the charging batteries and switchmechanism for the discharging batteries, a ground switch, cross connections between said switch mechanisms,

`a voltmeter connected directly with the charging fbattery switch mechanism, and an ammeter connected directly with the discharging battery switch mechanism, said charging battery switch mechanism and said ground switch controlling the connection of the voltnieter with the .*lischarging battery switch meclmnisin, and said discharging battery switch mechanism controlling the connection (it the amnietcr with the charging battery switch mechanism.

Qi. In a storage battery system, the combination of charging batteries and discharginglgiatteries, switch mechanism for the discharging batteries comprising switch contacts and a switch member, switch mechanism for the charging batteries comprising switch contacts and a switch member, auxiliary switch mechanism connected with contacts of the charging battery switch mechanisni, a voltmeter connected with contacts of the charging battery switch mechanism, said auxiliary switch mechanism being connected with contacts of the discharging battery switch mechanism, the switch member of said charging battery switch mechanism being constructed and arranged for alternate connection with the charging batteries and with the auxiliary switch mechanism.

In a storage battery system, the combination of charging batteries and discharging batteries, switch mechanism for the discharging batteries comprising switch, contacts and aswiteh member, switch mechanisni for the charging batteries comprising `switch contacts and a switch member, auxiliary switch mechanism connected with contacts'of the .charging battery switch mechamsm, a voltmeter connected with contacts of tno charging battery switch mechanism, said auxiliary switch mechanism being connected with contacts ot' the discharging hattcry switch mechanism, the switch member of the charging battery switch mechanism being constructed and arranged in one positionto disconnect the charging batteries from the contacts with which the voltineter i); connected and to connect such contacts with the auxiliary switch mechanism and said switch member arranged when in anposition to `canse entire disconnection 1 Voltniete'r contacts :from the auxiliary switch mechanisms and connection of said roltmeter contacts with charging batteries.

In a storage battery .system7 the com tra of n cliargiii battery and a d anisni ot' the charging battery switch mechanism,

the switch member of said charging batteryr switch mechanism being constructed and arranged when' moved into one position to entirely-disconncz; the voltnicter from the charging batteries and to connect the voltnieter with the auxiliary swttchmechanism whereby upon adjustment ot said auxiliary switch i'neclianism to its gri'uind connection, the voltineter will he in circuit to measure the potential between a terminal of the discharging batteries and ground. and upon adjustment of said charging battery switch member to another position the auxiliary switch mechanism 'will he entirely disconnected from the charging batter`- switen mechanism.

24. In a storage battery system, the combination of a charging battery and a discharging battery switch mechanism for the i discharging battery comprising switch corr tacts and a su itch member for interconnecting said contacts ritch mechanism for the charging battery comprising switch ctmtact and a switch member :for inter-connect-ingr said contacts, auxiliary switch. mechanism having conta( connected with contacts of the discharging battery switch mechanism and hai-'ing also grounded contacts,` said aiilxiliary switch. mechanism being connected with contacts oiif the charging battery switch inedianisin,said :mxiliary switch mechanism being adjustallilc to connect either terminal of the discharging battery withground or to connect the discharging battery terminals with the contacts of the charging hattery switch mechanism with which said auxiliary switch mechanism is' connecte-,rh a voltmeter connected with contacts of the charging battery switch mechanism, the switch member ot said charging battery switch when in another position to entirely disconnect the ufixiliary switch mechanism from itacts ott-he charging bat-J 1 w connect. auch hinat'ron of a charging battery anda dis'- eharging'battery, switch mechanism for the charging battery and switch mechanism for the discharging battery, said switch mechanisms being interconnected, and a voltmeter connected directly with the charging battery switch mechanism. the switchmechmism of the charging battery controlling the ccnnection otV the -roltmeter with the charging hattcry andthe switch mechanisms ,of both batteries.controlling together the nism of the discharging battery. said charge,

ing battery switch mechanism controlling di rectly the connection of the voltrneter with the charging battery, the switch mechanism for the discharging battery controlling di rectly the connection of thc"anmuter with the discharging battery. and hotli .switch mechanisms together controlling the conY ncction of the voltmctcr and a|nmelc:'rcspefjtivcly with the discharging and charging batteries.

27. 'ln a Storage battery system. the com bination of a charging battery and a dis charging battery, switch mechanism for the. char in -batteryand switch mechanism for the tiscarging battery, a circuit interconnecting said switch mechanisms, auxiliary switch mechanism lincluded. in such interconnecting circuit andhaving ground contacts whereby either terminal of the discharging batteryd may he connected with ground, a roltmcter connected with the switch mechanism of the charging battery, said charging battery switch mechanism be ing adjustable to cause' connection of the yoltmeter with the interconnecting circuit whereby the potential between ground and either terminal :,-i' the discharging battery mayy be determined. auch at'ljustmcnt of thivand ground.

chargingr battery switch mech asm Causing entire disconnection of theV charging batteries from the roltmeter and from the interconnecting circuit.

28. In a storage hatt-ery system, the combination of a discharging battery connected with a difazhargingr circuit. a -harginy b'attery connected with a charging circuit, switch mechanism for the discharging hattery, switch mechanism for the charging battery, a 'circuit interconnect ing aid switch mechanisms, auxiliary switch i'nechanism connected with such interconnecting circuit and adapted to connect either branch thereof and thereby either terminal of the discharging battery to ground. a yoltmeter connected with -the charging battery switch mechanism, and an ammetcr connected with the discharging battery switch mechanislm .said charging battery switch mechanism being adjustable to cause connection of the yoltmeter with the interconnecting circuit, and said discharging battery switch mecha: nism being adjustable to connect the discharging hattery with the interconnecting circuit whereby the potential can he deterniiucd between either terminal ofthe discharging buttery and ground, such adjustn'icnt ot' the discharging battery switch mechanilm cau-ing connection ofthe am# meter with the discharging battery circuit to indicatc thil current fiow through such circuit.

if). ln u storage battery system the conibination ofa charging battery and adischarging battery. a yoltn'ietcr. an annneter. means for Simultaneously connecting the voltmeter and annneter with either the charging or discharging battery.l and means for connecting theannneter with the discharging battery and i'or simultaneously connecting said roltmetcr in serieswith either terminnl ol' the discharging battery 

